Ratchet mechanism for winches



July 11, 1939. c c, M N 2,155,756

' 4 RATCHET MECHANISM FOR WINCHES Filed Aug. 20, 1938 N V IN VENTOR. I J1 B 0mm 55 6. MART/A A ATTORNEYS.

Patented July 11, 1939 UNITED STATES PATENT OFFICE Charles C. Martin,Cleveland Heights, Ohio, as-

signor to David Round & Son, Garfield Heights,

Ohio

Application August 20, 1938, Serial No. 225,945

6 Claims.

This invention, as indicated, relates to a ratchet mechanism forwinches. More particularly, it comprises a pawl and ratchet mechanismwhich in one position of the pawl permits rotation of the drum to takeup on the cable and hold the same against release, and in anotherposition of the pawl provides for free rotation of the drum of the winchwith the pawl positively held free of engagement with the ratchet teeth.

7 The invention includes features of construction providing a simplifiedand highly dependable mechanism of sturdy construction and of longservice life without attention.

In certain types of apparatus, particularly in connection withscrew-geared winches it is desirable to provide a ratchet mechanismpermitting free take-up of the cable on the drum during one period ofoperation and to free such drum of the ratchet mechanism during anotherstage of the operation. For each of the stages of operation referred toit is desirable to have the pawl positively held in operative position,or in inoperative position, so that no accidental movement of the pawlfrom one position'to the other will take place. This is of particularimportance where the winches areused on shipboard or on small watercraft inasmuchas the accidental movement of the pawl from one positionto the other may cause serious consequences. The mechanism herein setforth is designed to supply a pawl of simplified construction and ofdependable operative characteristics so that a winch provided with suchmechanism may be operated with a maximum of security.

The principal object of the present invention is to provide a ratchetmechanism for winches of simplified construction, but havingoperativeelements of sturdy and dependable character which will function reliablyunder conditions of heavy service requirements.

Another object of the invention is to provide a pawl and ratchetmechanism for winches wherein the pawl may be positively moved to op-.erative position, and may also be positively held in retracted positionwhen desired.

A further object of the invention is to provide a pawl and ratchetmechanism for winches wherein the pawl may be positioned adjacent thelower portion of the winch at a point free of in-- terference with othermechanism, and yet may be readily accessible for movement to operativeor inoperative position when required.

A further object of the invention is to provide a pawl and ratchetmechanism for winches wherein the pawl is positioned adjacent the lowerportion of the ratchet, and is provided with means for cooperating withthe base plate of the winch to hold such pawl resiliently in enagementwith the ratchet teeth in one position of adjustment or to positivelyhold such pawl out of engagement with the ratchet teeth in anotherposition of adjustment.

Other and further objects of the invention will appear in the course ofthe following description.

To the accomplishment of the foregoing and related ends, said invention,then, consists of the means hereinafter fully described and particularlypointed out in the claims, the annexed drawing and the followingdescription setting forth in detail certain mechanism embodying theinvention, such disclosed means constituting, however, but several ofvarious forms in which the principle of the invention may be used.

In said annexed drawing:

Fig. 1 is a fragmentary end elevation of a winch with a pawl and ratchetmechanism in operative engagement, as shown in dotted lines;

Fig. 2 is a fragmentaryside elevation of the end portion of a winchillustrating the pawl and ratchet mechanism, as shown in Fig. 1;

Fig. 3 is an enlarged fragmentary side elevation of the pawl and ratchetmechanism showing the base plate in section as seen along the line 3-3,shown in Fig. 2, looking in the direction of the arrows;

Fig. 4 is a View similar to Fig. 3 showing the pawl positively held in aposition disengaged from the ratchet; and

Fig. 5 is an enlarged detailed view taken along the line 55, shown inFig. 3, looking in the direction of the arrows.

As is clearly shown in Figs. 1 and 2, the winch comprises a base plate Iand an end plate 2 securely mounted thereon, said end plate beingprovided centrally with an aperture 3 forming a bearing for the stubshaft 4 forming a part of the drum assembly of the winch. The drum 5 hasan end flange 6, and outwardly thereof is provided with a ratchet member1 slightly spaced from the end flange 6, with its outer face in contactwith an anti-friction bearing within a stationary collar 8 secured tothe inner face of the end plate 2 by welding or other suitable means andmounted concentrically with the stub shaft 4 of the drum.

At a point adjacent one side of the end plate and approximately in thehorizontal plane of the lower margin of the ratchet wheel a boss II issecured by welding or other suitable means to the inner face of the endplate, the boss and plate being perforated and screw-threaded to receivea pivot bolt |2 having an enlarged bearing portion l3 over which anaperture M in the body of the pawl l5 may be engaged. The pivot bolt hasan integral screw-threaded stem section |6 adapted to be engaged by anut I'l bearing against the outer face of the end plate 2.

The body portion of the pawl is preferably in the form of a fiat platehaving the pivot opening |4 approximately centrally thereof, and havinga ratchet engaging terminal 2| at one end ther e-,v

of and a handle 22 at the opposite end thereof. In the form shown inFigs. 3 and 4, it will be noted that as seen from the side the pawl isin the form of a shallow inverted V with the pivot centrally thereof andthe handle section and ratchet terminal section meeting at an angle.

The terminal 2| is suitably shaped to provide an upwardly inclinedsurface 23 to conform sub: stantially to the adjacent beveled face 24 ofone of the ratchet teeth 25 which preferably have short flattened areas26 adjacent the end faces 21 of the ratchet teeth. The end surface'29 ofthe pawl preferably conforms to the end face of' the ratchet teeth, theradial angle of such surfaces in relation to the pivot of the pawlpreferably being such that a slight movement of the drum occurs when thepawl is moved to releasing position. In other words, the ratchetteeth'are in effect slightly undercut to provide continuous latchingengagement until the' pawl is moved manually to releasing position. Thislocking action is wholly independent'of the spring-toggle mechanismpresently to be described.

The handle 22 of the pawl projects beyond one side of the end plate 2 ofthe winch structure and is preferably shaped to be conveniently graspedby'the hand of the operator, as is clearly shown in Fig. 1 of thedrawing.

In orderto positively hold the pawl'in either ratchet engaging or inratchet releasing position;

a spring toggle mechanism "is provided, such structure comprising apivot plate 3| preferably formed as a'projection'on 'a head 32 having anintegral threaded'stem 33 adaptedto be engaged. in a threaded recess 34formed in the underside of the body of the pawl'somewhat in advance ofthe central vertical-plane of the pivot opening I l of the pawl towardthe ratchet engaging side thereof. The other parts of the spring togglemechanism comprise a pivoted "togglemember preferably in the fo'rm'ofash'ortcylindrical bar slot 36 and a pivot pin 39 is engaged throughsaid alined apertures. The ends of the pivoted members are rounded topermit free pivotal move ment of the parts when'the pawl is'shifted aswill' be presently explained;

As has been indicated, the upper end of the spring 38 is engaged withinthe spring housing 31 in the toggle bar 35. The lower end of the spring,as is'shown more particularly in Figs. 3, 4' and 5, is received within ashallow recess 4| formed in the base plate I of the winch' at a pointoffset slightly from the vertical plane through the pivot opening I4 ofthe'pawl, in a direction toward the handle end of the pawl.

The spring 38 is preferably made of slightly spaced turns of wire ofsuitable gauge and of a normally extended length greater than thedistance between the bottom of the recess 4| in the base plate and thebottom of the recess 31, so that the spring will be constantly undercompression when assembled in the spring-toggle mechanism. The spacingof the spring coils is such as to permit further compression of thespring as the pawl is moved from engaged to released position with thespring reaching maximum compression as the spring-toggle mechanismpasses dead center.

By reason of the construction just explained the spring acts/against thepawl first on one side of the pivot of the pawl, and then, when the pawlis manually moved, to its opposite position, on the opposite side of thepivot of the pawl. While the pawl has a wide range of movement fromengaged to released position, it will be noted that the spring-toggleelements have relatively small range of movement. The coil spring 38itself forms an active structural part of the springtoggle mechanismobviating the necessity of a pivot pin at the'lower end of the togglelinkage, and affording a most simple and convenient means of assembly ofthe parts. It provides a minimum of structural elements and a base plateentirely free of pivot ears or bosses, which have a 'tendency toaccumulate foreign matter in the restricted space and thus requireconstant examination to insure the dependable operation of theapparatus.

It will be noted that the ratchet wheel provides the upper limit ofmotion for the pawl and that the spring-toggle provides for resilientengagement of the pawl terminal 2| with ratchet teeth successively asthe winch is turned in cable winding direction. When the pawl inretracted or releasing position, the base plate I, as shown in Fig. 4,provides the stop at the lower limit of motion, the lower edge of thepawl terminal contacting the base plate.

'While the ratchet terminal end of the pawl could be made heavy enoughto move to retracted position when released, where the device is used onshipboard, it is desirable to positively hold the pawl in retracted aswell as in engaged position, and both of these functions are'served bythe double acting spring-toggle structure herein provided.

Other modes of applying the principle of my invention may be employedinstead of those explained, change being made as regards the mechanismherein disclosed, provided the means stated by any of the followingclaimsor the equivalent of such stated means be employed.

I therefore particularly point out and distinctly claim as myinvention:-

1. An apparatus of the character described having in combination, awinch drum carrying a ratchet wheel at one end, a supporting frame forsaid winch having a base plate and having an end plate in spacedrelation to said ratchet wheel, a stub shaft projecting axially fromsaid winch drum and received in a suitable aperture in said end plate, apawl pivotallymounted on said end plate adjacent the forward lowercorner thereof and. having one end portion projecting beyond said endplate to provide a handle and the opposite end portion projectingbeneath the ratchet wheel, and resilient means mounted on said baseplate for selectively holding said pawl in engagement with said ratchetwheel and in retracted position.

2. An apparatus of the character described having in combination, awinch drum carrying a ratchet wheel at one end, a supporting frame forsaid Winch having a base plate and having an end plate in spacedrelation to said ratchet wheel, a stub shaft projecting axially fromsaid winch drum and received in a suitable aperture in said end plate, apawl pivotally mounted on said end plate adjacent the forward lowercorner thereof and having one end portion projecting beyond said endplate to provide a handle and the opposite end portion projectingbeneath the ratchet wheel, and a spring toggle unit positionedintermediate said base plate and pawl structure for selectively holdingsaid pawl in engagement with said ratchet Wheel and in retractedposition.

3. An apparatus of the character described having in combination, aratchet wheel associated with a winch mechanism, a Supporting framehaving a base plate and end plate for said mechanism, an elongated platehaving one end pivoted at a central point to said end plate and havingone end projecting beneath said ratchet wheel with the opposite endprojecting beyond said end plate to provide an operative handle, and aspring toggle mechanism interposed between the elongated plate and thebase plate to selectively hold said projecting end of the plate inengagenism, an elongated plate having one end pivoted at a central pointto said end plate and having one end projecting beneath said ratchetwheel with the opposite end projecting beyond said end plate to providean operative handle, a spring receiving sleeve hingedly secured to theunder side of said lever adjacent the central pivot of the lever, and acoil spring having one end engaged within said sleeve and its oppositeend engaged within a recess provided in said base plate substantially inalinement with the pivot of said elongated plate, said spring and hingedsleeve forming a spring toggle for selectively holding the active end ofsaid lever in engagement with said ratchet wheel or in retractedposition.

5. An apparatus of the character described having in combination, asupporting frame in-. cluding a base plate and an end plate, a ratchetwheel associated with a winch drum positioned in spaced relation to saidend plate, a stub shaft on said winch drum for pivotally supporting saidwinch unit in said end plate, an elongated plate providing a handle atone end and a pawl at the opposite end for active engagement with saidratchet wheel, means centrally of said plate for pivotally supportingthe same for movement into and out of engagement with said ratchetwheel, and a spring toggle mechanism interposed between said plate andsaid frame for actuating said plate, said spring toggle mechanismcomprising a hinged member providing a housing for one end of a coilspring and a coil spring engaged in said housing with its free endreceived in a recess in one of the abutting members.

6. An apparatus of the character described having in combination, asupporting frame including a base plate and an end plate, a ratchetwheel associated with a winch drum positioned in spaced relation to saidend plate, a stub shaft on said winch drum for pivotally supporting saidwinchunit in said end plate, an anti-friction bearing interposed betweensaid end plate and said ratchet wheel concentric with said stub shaft,an elongated plate providing a handle at one end and a pawl at theopposite end for active engagement with said ratchet wheel, meanscentrally of said plate for pivotally supporting the same for movementinto and out of engagement with said ratchet wheel, and a spring togglemechanism interposed between said plate and said frame for actuatingsaid plate, said spring toggle mechanism comprising a hinged memberproviding a housing for one end of a coil spring and a coil springengaged in said housing with its free end received in a recess in one ofthe abutting members, the hinged portion of said spring toggle mechanismbeing positioned beneath the pivot of said elongated plate and adaptedto be moved past dead center to either side thereof to selectively holdsaid pawl terminal of said plate in engagement with said ratchet wheelor in retracted position.

CHARLES C. MARTIN.

